Paraprotein-related renal disease and amyloid

Paraproteins are produced by a wide spectrum of haematological conditions, most commonly by plasma cell dyscrasias. Paraprotein production is frequently incidental in patients with renal disease but can directly cause renal impairment through a variety of underlying pathological processes. Diagnosis is usually through the detection of a monoclonal protein, either in the serum or urine. Monoclonal free light chain assays are more sensitive than electrophoresis or immunofixation and are useful in monitoring clonal response to treatment. Renal biopsy is necessary to establish a definitive diagnosis. The general supportive management of all paraprotein-related renal lesions is meticulous fluid balance, early treatment of infections and avoidance of nephrotoxic insults. Patients with severe renal impairment may require renal replacement therapy and selected patients can benefit from renal transplantation. Treatment with chemotherapy can halt the production of the paraprotein and thus progressive renal damage. Early diagnosis and use of the newer rapidly effective chemotherapy agents has improved patient and renal outcomes.